New solid object bouncing, and updated player bouncing

- Solid objects have new bouncing physics, it's a mix of the object bumping and wall bumping. It replaces the "solid" option on K_KartBouncing.
- Goomba stomp momentum is decided in K_KartBouncing itself instead of needing to be manually passed in as a boolean, so you'll be able to goomba stomp all objects instead of just players.
- Fixed bumping not carrying all of its intended momentum, due to a bug making friction apply very strongly.

src/k_collide.c

@@ -46,7 +46,7 @@ boolean K_OrbinautJawzCollide(mobj_t *t1, mobj_t *t2)
 		{
 			// Player Damage
 			P_DamageMobj(t2, t1, t1->target, 1, DMG_WIPEOUT);
-			K_KartBouncing(t2, t1, false, false);
+			K_KartBouncing(t2, t1);
 			S_StartSound(t2, sfx_s3k7b);
 		}
 
@@ -430,7 +430,7 @@ boolean K_KitchenSinkCollide(mobj_t *t1, mobj_t *t2)
 boolean K_FallingRockCollide(mobj_t *t1, mobj_t *t2)
 {
 	if (t2->player || t2->type == MT_FALLINGROCK)
-		K_KartBouncing(t2, t1, false, false);
+		K_KartBouncing(t2, t1);
 	return true;
 }
 
@@ -457,8 +457,8 @@ boolean K_SMKIceBlockCollide(mobj_t *t1, mobj_t *t2)
 		return true;
 	*/
 
-	K_KartBouncing(t2, t1, false, true);
+	K_KartSolidBounce(t1, t2);
-	return false;
+	return true;
 }
 
 boolean K_PvPTouchDamage(mobj_t *t1, mobj_t *t2)
@@ -537,25 +537,24 @@ boolean K_PvPTouchDamage(mobj_t *t1, mobj_t *t2)
 
 	if (t1Condition == true)
 	{
+		P_PlayerRingBurst(t2->player, 1);
+
 		if (t2->player->rings <= 0)
 		{
 			P_DamageMobj(t2, t1, t1, 1, DMG_STING);
 			stung = true;
 		}
-
-		P_PlayerRingBurst(t2->player, 1);
-		stung = true;
 	}
 
 	if (t2Condition == true)
 	{
+		P_PlayerRingBurst(t1->player, 1);
+
 		if (t1->player->rings <= 0)
 		{
 			P_DamageMobj(t1, t2, t2, 1, DMG_STING);
 			stung = true;
 		}
-
-		P_PlayerRingBurst(t2->player, 1);
 	}
 
 	return stung;

src/k_kart.c

@@ -1123,16 +1123,137 @@ fixed_t K_GetMobjWeight(mobj_t *mobj, mobj_t *against)
 	return FixedMul(weight, mobj->scale);
 }
 
-boolean K_KartBouncing(mobj_t *mobj1, mobj_t *mobj2, boolean bounce, boolean solid)
+static void K_SpawnBumpForObjs(mobj_t *mobj1, mobj_t *mobj2)
 {
-	mobj_t *fx;
+	mobj_t *fx = P_SpawnMobj(
+		mobj1->x/2 + mobj2->x/2,
+		mobj1->y/2 + mobj2->y/2,
+		mobj1->z/2 + mobj2->z/2,
+		MT_BUMP
+	);
+	fixed_t avgScale = (mobj1->scale + mobj2->scale) / 2;
+
+	if (mobj1->eflags & MFE_VERTICALFLIP)
+	{
+		fx->eflags |= MFE_VERTICALFLIP;
+	}
+	else
+	{
+		fx->eflags &= ~MFE_VERTICALFLIP;
+	}
+
+	P_SetScale(fx, (fx->destscale = avgScale));
+
+	if ((mobj1->player && mobj1->player->itemtype == KITEM_BUBBLESHIELD)
+	|| (mobj2->player && mobj2->player->itemtype == KITEM_BUBBLESHIELD))
+	{
+		S_StartSound(mobj1, sfx_s3k44);
+	}
+	else
+	{
+		S_StartSound(mobj1, sfx_s3k49);
+	}
+}
+
+static void K_PlayerJustBumped(player_t *player)
+{
+	mobj_t *playerMobj = NULL;
+
+	if (player == NULL)
+	{
+		return;
+	}
+
+	playerMobj = player->mo;
+
+	if (playerMobj == NULL || P_MobjWasRemoved(playerMobj))
+	{
+		return;
+	}
+
+	if (abs(player->rmomx) < playerMobj->scale && abs(player->rmomy) < playerMobj->scale)
+	{
+		// Because this is done during collision now, rmomx and rmomy need to be recalculated
+		// so that friction doesn't immediately decide to stop the player if they're at a standstill
+		player->rmomx = playerMobj->momx - player->cmomx;
+		player->rmomy = playerMobj->momy - player->cmomy;
+	}
+
+	player->justbumped = bumptime;
+	player->spindash = 0;
+
+	if (player->spinouttimer)
+	{
+		player->wipeoutslow = wipeoutslowtime+1;
+		player->spinouttimer = max(wipeoutslowtime+1, player->spinouttimer);
+		//player->spinouttype = KSPIN_WIPEOUT; // Enforce type
+	}
+}
+
+static fixed_t K_GetBounceForce(mobj_t *mobj1, mobj_t *mobj2, fixed_t distx, fixed_t disty)
+{
+	const fixed_t forceMul = (4 * FRACUNIT) / 10; // Multiply by this value to make it feel like old bumps.
+
 	fixed_t momdifx, momdify;
-	fixed_t distx, disty;
+	fixed_t dot;
-	fixed_t dot, force;
+	fixed_t force = 0;
+
+	momdifx = mobj1->momx - mobj2->momx;
+	momdify = mobj1->momy - mobj2->momy;
+
+	if (distx == 0 && disty == 0)
+	{
+		// if there's no distance between the 2, they're directly on top of each other, don't run this
+		return 0;
+	}
+
+	{ // Normalize distance to the sum of the two objects' radii, since in a perfect world that would be the distance at the point of collision...
+		fixed_t dist = P_AproxDistance(distx, disty);
+		fixed_t nx, ny;
+
+		dist = dist ? dist : 1;
+
+		nx = FixedDiv(distx, dist);
+		ny = FixedDiv(disty, dist);
+
+		distx = FixedMul(mobj1->radius + mobj2->radius, nx);
+		disty = FixedMul(mobj1->radius + mobj2->radius, ny);
+
+		if (momdifx == 0 && momdify == 0)
+		{
+			// If there's no momentum difference, they're moving at exactly the same rate. Pretend they moved into each other.
+			momdifx = -nx;
+			momdify = -ny;
+		}
+	}
+
+	dot = FixedMul(momdifx, distx) + FixedMul(momdify, disty);
+
+	if (dot >= 0)
+	{
+		// They're moving away from each other
+		return 0;
+	}
+
+	// Return the push force!
+	force = FixedDiv(dot, FixedMul(distx, distx) + FixedMul(disty, disty));
+
+	return FixedMul(force, forceMul);
+}
+
+boolean K_KartBouncing(mobj_t *mobj1, mobj_t *mobj2)
+{
+	const fixed_t minBump = 25*mapobjectscale;
+	mobj_t *goombaBounce = NULL;
+	fixed_t distx, disty, dist;
+	fixed_t force;
 	fixed_t mass1, mass2;
 
-	if (!mobj1 || !mobj2)
+	if ((!mobj1 || P_MobjWasRemoved(mobj1))
+	|| (!mobj2 || P_MobjWasRemoved(mobj2)))
+	{
 		return false;
+	}
 
 	// Don't bump when you're being reborn
 	if ((mobj1->player && mobj1->player->playerstate != PST_LIVE)
@@ -1176,135 +1297,145 @@ boolean K_KartBouncing(mobj_t *mobj1, mobj_t *mobj2, boolean bounce, boolean sol
 		return false;
 	}
 
-	mass1 = K_GetMobjWeight(mobj1, mobj2);
+	// Adds the OTHER object's momentum times a bunch, for the best chance of getting the correct direction
+	distx = (mobj1->x + mobj2->momx) - (mobj2->x + mobj1->momx);
+	disty = (mobj1->y + mobj2->momy) - (mobj2->y + mobj1->momy);
 
-	if (solid == true && mass1 > 0)
+	force = K_GetBounceForce(mobj1, mobj2, distx, disty);
-		mass2 = mass1;
-	else
-		mass2 = K_GetMobjWeight(mobj2, mobj1);
 
-	momdifx = mobj1->momx - mobj2->momx;
+	if (force == 0)
-	momdify = mobj1->momy - mobj2->momy;
-
-	// Adds the OTHER player's momentum times a bunch, for the best chance of getting the correct direction
-	distx = (mobj1->x + mobj2->momx*3) - (mobj2->x + mobj1->momx*3);
-	disty = (mobj1->y + mobj2->momy*3) - (mobj2->y + mobj1->momy*3);
-
-	if (distx == 0 && disty == 0)
 	{
-		// if there's no distance between the 2, they're directly on top of each other, don't run this
 		return false;
 	}
 
-	{ // Normalize distance to the sum of the two objects' radii, since in a perfect world that would be the distance at the point of collision...
+	mass1 = K_GetMobjWeight(mobj1, mobj2);
-		fixed_t dist = P_AproxDistance(distx, disty);
+	mass2 = K_GetMobjWeight(mobj2, mobj1);
-		fixed_t nx, ny;
 
-		dist = dist ? dist : 1;
+	if ((P_IsObjectOnGround(mobj1) && mobj2->momz < 0) // Grounded
-
+		|| (mass2 == 0 && mass1 > 0)) // The other party is immovable
-		nx = FixedDiv(distx, dist);
+	{
-		ny = FixedDiv(disty, dist);
+		goombaBounce = mobj2;
-
-		distx = FixedMul(mobj1->radius+mobj2->radius, nx);
-		disty = FixedMul(mobj1->radius+mobj2->radius, ny);
-
-		if (momdifx == 0 && momdify == 0)
-		{
-			// If there's no momentum difference, they're moving at exactly the same rate. Pretend they moved into each other.
-			momdifx = -nx;
-			momdify = -ny;
-		}
 	}
+	else if ((P_IsObjectOnGround(mobj2) && mobj1->momz < 0) // Grounded
+		|| (mass1 == 0 && mass2 > 0)) // The other party is immovable
+	{
+		goombaBounce = mobj1;
+	}
+
+	if (goombaBounce != NULL)
+	{
+		// Perform a Goomba Bounce by reversing your z momentum.
+		goombaBounce->momz = -goombaBounce->momz;
+	}
+	else
+	{
+		// Trade z momentum values.
+		fixed_t newz = mobj1->momz;
+		mobj1->momz = mobj2->momz;
+		mobj2->momz = newz;
+	}
+
+	// Multiply by force
+	distx = FixedMul(force, distx);
+	disty = FixedMul(force, disty);
+	dist = FixedHypot(distx, disty);
 
 	// if the speed difference is less than this let's assume they're going proportionately faster from each other
-	if (P_AproxDistance(momdifx, momdify) < (25*mapobjectscale))
+	if (dist < minBump)
 	{
-		fixed_t momdiflength = P_AproxDistance(momdifx, momdify);
+		fixed_t normalisedx = FixedDiv(distx, dist);
-		fixed_t normalisedx = FixedDiv(momdifx, momdiflength);
+		fixed_t normalisedy = FixedDiv(disty, dist);
-		fixed_t normalisedy = FixedDiv(momdify, momdiflength);
-		momdifx = FixedMul((25*mapobjectscale), normalisedx);
-		momdify = FixedMul((25*mapobjectscale), normalisedy);
-	}
 
-	dot = FixedMul(momdifx, distx) + FixedMul(momdify, disty);
+		distx = FixedMul(minBump, normalisedx);
-
+		disty = FixedMul(minBump, normalisedy);
-	if (dot >= 0)
-	{
-		// They're moving away from each other
-		return false;
-	}
-
-	force = FixedDiv(dot, FixedMul(distx, distx)+FixedMul(disty, disty));
-
-	if (bounce == true && mass2 > 0) // Perform a Goomba Bounce.
-		mobj1->momz = -mobj1->momz;
-	else
-	{
-		fixed_t newz = mobj1->momz;
-		if (mass2 > 0)
-			mobj1->momz = mobj2->momz;
-		if (mass1 > 0 && solid == false)
-			mobj2->momz = newz;
 	}
 
 	if (mass2 > 0)
 	{
-		mobj1->momx = mobj1->momx - FixedMul(FixedMul(FixedDiv(2*mass2, mass1 + mass2), force), distx);
+		mobj1->momx = mobj1->momx - FixedMul(FixedDiv(2*mass2, mass1 + mass2), distx);
-		mobj1->momy = mobj1->momy - FixedMul(FixedMul(FixedDiv(2*mass2, mass1 + mass2), force), disty);
+		mobj1->momy = mobj1->momy - FixedMul(FixedDiv(2*mass2, mass1 + mass2), disty);
 	}
 
-	if (mass1 > 0 && solid == false)
+	if (mass1 > 0)
 	{
-		mobj2->momx = mobj2->momx - FixedMul(FixedMul(FixedDiv(2*mass1, mass1 + mass2), force), -distx);
+		mobj2->momx = mobj2->momx - FixedMul(FixedDiv(2*mass1, mass1 + mass2), -distx);
-		mobj2->momy = mobj2->momy - FixedMul(FixedMul(FixedDiv(2*mass1, mass1 + mass2), force), -disty);
+		mobj2->momy = mobj2->momy - FixedMul(FixedDiv(2*mass1, mass1 + mass2), -disty);
 	}
 
-	// Do the bump fx when we've CONFIRMED we can bump.
+	K_SpawnBumpForObjs(mobj1, mobj2);
-	if ((mobj1->player && mobj1->player->itemtype == KITEM_BUBBLESHIELD) || (mobj2->player && mobj2->player->itemtype == KITEM_BUBBLESHIELD))
-		S_StartSound(mobj1, sfx_s3k44);
-	else
-		S_StartSound(mobj1, sfx_s3k49);
 
-	fx = P_SpawnMobj(mobj1->x/2 + mobj2->x/2, mobj1->y/2 + mobj2->y/2, mobj1->z/2 + mobj2->z/2, MT_BUMP);
+	K_PlayerJustBumped(mobj1->player);
-	if (mobj1->eflags & MFE_VERTICALFLIP)
+	K_PlayerJustBumped(mobj2->player);
-		fx->eflags |= MFE_VERTICALFLIP;
-	else
-		fx->eflags &= ~MFE_VERTICALFLIP;
-	P_SetScale(fx, mobj1->scale);
 
-	// Because this is done during collision now, rmomx and rmomy need to be recalculated
+	return true;
-	// so that friction doesn't immediately decide to stop the player if they're at a standstill
+}
-	// Also set justbumped here
+
-	if (mobj1->player)
+// K_KartBouncing, but simplified to act like P_BouncePlayerMove
+boolean K_KartSolidBounce(mobj_t *bounceMobj, mobj_t *solidMobj)
+{
+	const fixed_t minBump = 25*mapobjectscale;
+	fixed_t distx, disty, dist;
+	fixed_t force;
+
+	if ((!bounceMobj || P_MobjWasRemoved(bounceMobj))
+	|| (!solidMobj || P_MobjWasRemoved(solidMobj)))
 	{
-		mobj1->player->rmomx = mobj1->momx - mobj1->player->cmomx;
+		return false;
-		mobj1->player->rmomy = mobj1->momy - mobj1->player->cmomy;
-		mobj1->player->justbumped = bumptime;
-		mobj1->player->spindash = 0;
-
-		if (mobj1->player->spinouttimer)
-		{
-			mobj1->player->wipeoutslow = wipeoutslowtime+1;
-			mobj1->player->spinouttimer = max(wipeoutslowtime+1, mobj1->player->spinouttimer);
-			//mobj1->player->spinouttype = KSPIN_WIPEOUT; // Enforce type
-		}
 	}
 
-	if (mobj2->player)
+	// Don't bump when you're being reborn
+	if (bounceMobj->player && bounceMobj->player->playerstate != PST_LIVE)
+		return false;
+
+	if (bounceMobj->player && bounceMobj->player->respawn.state != RESPAWNST_NONE)
+		return false;
+
+	// Don't bump if you've recently bumped
+	if (bounceMobj->player && bounceMobj->player->justbumped)
 	{
-		mobj2->player->rmomx = mobj2->momx - mobj2->player->cmomx;
+		bounceMobj->player->justbumped = bumptime;
-		mobj2->player->rmomy = mobj2->momy - mobj2->player->cmomy;
+		return false;
-		mobj2->player->justbumped = bumptime;
-		mobj2->player->spindash = 0;
-
-		if (mobj2->player->spinouttimer)
-		{
-			mobj2->player->wipeoutslow = wipeoutslowtime+1;
-			mobj2->player->spinouttimer = max(wipeoutslowtime+1, mobj2->player->spinouttimer);
-			//mobj2->player->spinouttype = KSPIN_WIPEOUT; // Enforce type
-		}
 	}
 
+	// Adds the OTHER object's momentum times a bunch, for the best chance of getting the correct direction
+	{
+		distx = (bounceMobj->x + solidMobj->momx) - (solidMobj->x + bounceMobj->momx);
+		disty = (bounceMobj->y + solidMobj->momy) - (solidMobj->y + bounceMobj->momy);
+	}
+
+	force = K_GetBounceForce(bounceMobj, solidMobj, distx, disty);
+
+	if (force == 0)
+	{
+		return false;
+	}
+
+	// Multiply by force
+	distx = FixedMul(force, distx);
+	disty = FixedMul(force, disty);
+	dist = FixedHypot(distx, disty);
+
+	{
+		// Normalize to the desired push value.
+		fixed_t normalisedx = FixedDiv(distx, dist);
+		fixed_t normalisedy = FixedDiv(disty, dist);
+		fixed_t bounceSpeed;
+
+		bounceSpeed = FixedHypot(bounceMobj->momx, bounceMobj->momy);
+		bounceSpeed = FixedMul(bounceSpeed, (FRACUNIT - (FRACUNIT>>2) - (FRACUNIT>>3)));
+		bounceSpeed += minBump;
+
+		distx = FixedMul(bounceSpeed, normalisedx);
+		disty = FixedMul(bounceSpeed, normalisedy);
+	}
+
+	bounceMobj->momx = bounceMobj->momx - distx;
+	bounceMobj->momy = bounceMobj->momy - disty;
+	bounceMobj->momz = -bounceMobj->momz;
+
+	K_SpawnBumpForObjs(bounceMobj, solidMobj);
+	K_PlayerJustBumped(bounceMobj->player);
+
 	return true;
 }
 

src/k_kart.h

@@ -37,7 +37,8 @@ UINT8 K_FindUseodds(player_t *player, fixed_t mashed, UINT32 pdis, UINT8 bestbum
 INT32 K_KartGetItemOdds(UINT8 pos, SINT8 item, fixed_t mashed, boolean spbrush, boolean bot, boolean rival);
 INT32 K_GetShieldFromItem(INT32 item);
 fixed_t K_GetMobjWeight(mobj_t *mobj, mobj_t *against);
-boolean K_KartBouncing(mobj_t *mobj1, mobj_t *mobj2, boolean bounce, boolean solid);
+boolean K_KartBouncing(mobj_t *mobj1, mobj_t *mobj2);
+boolean K_KartSolidBounce(mobj_t *bounceMobj, mobj_t *solidMobj);
 void K_KartPainEnergyFling(player_t *player);
 void K_FlipFromObject(mobj_t *mo, mobj_t *master);
 void K_MatchGenericExtraFlags(mobj_t *mo, mobj_t *master);

src/lua_baselib.c

@@ -3381,14 +3381,12 @@ static int lib_kKartBouncing(lua_State *L)
 {
 	mobj_t *mobj1 = *((mobj_t **)luaL_checkudata(L, 1, META_MOBJ));
 	mobj_t *mobj2 = *((mobj_t **)luaL_checkudata(L, 2, META_MOBJ));
-	boolean bounce = lua_optboolean(L, 3);
-	boolean solid = lua_optboolean(L, 4);
 	NOHUD
 	if (!mobj1)
 		return LUA_ErrInvalid(L, "mobj_t");
 	if (!mobj2)
 		return LUA_ErrInvalid(L, "mobj_t");
-	K_KartBouncing(mobj1, mobj2, bounce, solid);
+	K_KartBouncing(mobj1, mobj2);
 	return 0;
 }
 

src/p_map.c

@@ -1247,33 +1247,19 @@ static boolean PIT_CheckThing(mobj_t *thing)
 				return true;
 			}
 
+			// The bump has to happen last
+			if (P_IsObjectOnGround(thing) && tmthing->momz < 0 && tmthing->player->trickpanel)
 			{
-				// The bump has to happen last
+				P_DamageMobj(thing, tmthing, tmthing, 1, DMG_WIPEOUT|DMG_STEAL);
-				mobj_t *mo1 = tmthing;
+			}
-				mobj_t *mo2 = thing;
+			else if (P_IsObjectOnGround(tmthing) && thing->momz < 0 && thing->player->trickpanel)
-				boolean zbounce = false;
+			{
+				P_DamageMobj(tmthing, thing, thing, 1, DMG_WIPEOUT|DMG_STEAL);
+			}
 
-				if (P_IsObjectOnGround(thing) && tmthing->momz < 0)
+			if (K_KartBouncing(tmthing, thing) == true)
-				{
+			{
-					zbounce = true;
+				K_PvPTouchDamage(tmthing, thing);
-					mo1 = thing;
-					mo2 = tmthing;
-
-					if (tmthing->player->trickpanel)
-						P_DamageMobj(thing, tmthing, tmthing, 1, DMG_WIPEOUT|DMG_STEAL);
-				}
-				else if (P_IsObjectOnGround(tmthing) && thing->momz < 0)
-				{
-					zbounce = true;
-
-					if (thing->player->trickpanel)
-						P_DamageMobj(tmthing, thing, thing, 1, DMG_WIPEOUT|DMG_STEAL);
-				}
-
-				if (K_KartBouncing(mo1, mo2, zbounce, false))
-				{
-					K_PvPTouchDamage(mo1, mo2);
-				}
 			}
 
 			return true;
@@ -1300,8 +1286,8 @@ static boolean PIT_CheckThing(mobj_t *thing)
 			}
 			else
 			{
-				K_KartBouncing(tmthing, thing, false, true);
+				K_KartSolidBounce(tmthing, thing);
-				return false;
+				return true;
 			}
 		}
 		else if (thing->type == MT_SMK_PIPE)
@@ -1322,8 +1308,8 @@ static boolean PIT_CheckThing(mobj_t *thing)
 				return true; // kill
 			}
 
-			K_KartBouncing(tmthing, thing, false, true);
+			K_KartSolidBounce(tmthing, thing);
-			return false;
+			return true;
 		}
 		else if (thing->type == MT_SMK_THWOMP)
 		{
@@ -1362,12 +1348,13 @@ static boolean PIT_CheckThing(mobj_t *thing)
 				P_DamageMobj(tmthing, thing, thing, 1, DMG_TUMBLE);
 			else
 			{
-				if (thing->flags2 & MF2_AMBUSH)
+				if ((K_KartSolidBounce(tmthing, thing) == true) && (thing->flags2 & MF2_AMBUSH))
+				{
 					P_DamageMobj(tmthing, thing, thing, 1, DMG_WIPEOUT);
-				K_KartBouncing(tmthing, thing, false, true);
+				}
 			}
 
-			return false;
+			return true;
 		}
 		else if (thing->type == MT_KART_LEFTOVER)
 		{
@@ -1377,12 +1364,8 @@ static boolean PIT_CheckThing(mobj_t *thing)
 			if (tmthing->z + tmthing->height < thing->z)
 				return true; // underneath
 
-			if (P_IsObjectOnGround(thing) && tmthing->momz < 0)
+			K_KartBouncing(tmthing, thing);
-				K_KartBouncing(tmthing, thing, true, false);
+			return true;
-			else
-				K_KartBouncing(tmthing, thing, false, false);
-
-			return false;
 		}
 		else if (thing->flags & MF_SOLID)
 		{
@@ -1392,12 +1375,8 @@ static boolean PIT_CheckThing(mobj_t *thing)
 			if (tmthing->z + tmthing->height < thing->z)
 				return true; // underneath
 
-			if (P_IsObjectOnGround(thing) && tmthing->momz < 0)
+			K_KartSolidBounce(tmthing, thing);
-				K_KartBouncing(tmthing, thing, true, true);
+			return true;
-			else
-				K_KartBouncing(tmthing, thing, false, true);
-
-			return false;
 		}
 	}